Bilbao, AmaiaGarcía-Pérez, LidiaArenaza , Juan CarlosGarcía, IsidoroAriza-Cardiel , GloriaTrujillo-Martín, ElisaForjaz , Maria JoaoMartín Fernández, Jesús2025-01-072025-01-072018-07-05Bilbao, A., García-Pérez, L., Arenaza, J.C. et al. Psychometric properties of the EQ-5D-5L in patients with hip or knee osteoarthritis: reliability, validity and responsiveness. Qual Life Res 27, 2897–2908 (2018). https://doi.org/10.1007/s11136-018-1929-x0962-9343 (print)1573-2649 (online)https://hdl.handle.net/10115/50617This study was supported in part by grants from the Carlos III Health Institute (PI13/00560, PI13/00518 and PI13/00648) and the European Regional Development Fund.Purpose: To study the psychometric properties, including reliability, validity and responsiveness, of the Spanish EQ-5D-5L questionnaire for patients with hip or knee osteoarthritis (OA). Methods: We included 758 patients with hip or knee OA who completed the EQ-5D-5L and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at baseline, of whom 644 also did 6 months later. The EQ-5D-5L contains five questions from which a utility index is derived. The WOMAC covers three dimensions: pain, stiffness and physical function. Floor and ceiling effects were calculated. Reliability was assessed using Cronbach's alpha. Convergent validity was tested using the Spearman correlation coefficient between EQ-5D-5L and WOMAC. We examined known-groups validity by comparing the EQ-5D-5L between subgroups defined by WOMAC scores using ANOVA or the Kruskal-Wallis test. Effect sizes were calculated to assess responsiveness, and minimal clinically important difference (MCID) was estimated. Results: The EQ-5D-5L showed minimal floor and ceiling effects (< 3%). Cronbach's alpha was 0.86. The EQ-5D-5L index was strongly correlated with WOMAC pain and function scores (- 0.688 and - 0.782). Patients with higher WOMAC scores had significantly (p < 0.0001) lower EQ-5D-5L index. The 20.19% had hip or knee replacement during the follow-up. Effect sizes were small among non-surgical patients, but > 0.80 among "improved" surgical patients, being the MCID for improvement 0.32 points. Conclusions: The results support the reliability, validity and responsiveness of the EQ-5D-5L, overcoming the limitations of the EQ-5D-3L in these patients. Therefore, the EQ-5D-5L could be very useful as an outcome measure, at least in patients with hip or knee OA.enEQ-5D-5LMinimal clinically important differenceOsteoarthritisPsychometric propertiesUtility indexArticle10.1007/s11136-018-1929-xinfo:eu-repo/semantics/closedAccess